Charged particle beam accelerators have found wide usage in medical accelerators where the high energy beam is employed directly or indirectly, to generate x-rays, for therapeutic and diagnostic purposes. The electron beam generated by an accelerator can also be used directly or indirectly to kill infectious pests, to sterilize objects, to change physical properties of objects, and to perform testing and inspection of objects, such as containers, vehicles or concrete structures storing radioactive or nuclear material, or contraband.
In many applications, it is desirable that the energy of the electron beam be switchable readily and reliably. It is also desirable, in certain applications, that the switching of the beam energy be performed quickly, e.g., in a time interval on the order of milliseconds.